There are many adjectives one might use to describe the force of nature that is Twyla Tharp. At the opening of her current show at New York’s Joyce Theater, her dancers went to escort the 82-year-old choreographer onto the stage for a bow — but she was in more of a rush, bounding out from the wings in her black leathery pants and boots. Try to get a ticket to “Twyla Tharp Dance,” a two-week engagement, and you’ll likely see “sold out” (it’s worth the try anyway) — a testament to the enduring ent